Abstract
Remote photoplethysmography (rPPG) has emerged as a promising non-invasive method for monitoring physiological signals using the camera. Although various domain adaptation and generalization methods were proposed to promote the adaptability of deep-based rPPG models in unseen deployment environments, considerations in aspects like privacy concerns and real-time adaptation restrict their application in real-world deployment. Thus, we aim to propose a novel fully Test-Time Adaptation (TTA) strategy tailored for rPPG tasks in this work. Specifically, based on prior knowledge in physiology and our observations, we noticed not only there is spatio-temporal consistency in the frequency domain of rPPG signals, but also that inconsistency in the time domain was significant. Given this, by leveraging both consistency and inconsistency priors, we introduce an innovative expert knowledge-based self-supervised \textbf{C}onsistency-\textbf{i}n\textbf{C}onsistency-\textbf{i}ntegration (\textbf{CiCi}) framework to enhances model adaptation during inference. Besides, our approach further incorporates a gradient dynamic control mechanism to mitigate potential conflicts between priors, ensuring stable adaptation across instances. Through extensive experiments on five diverse datasets under the TTA protocol, our method consistently outperforms existing techniques, presenting state-of-the-art performance in real-time self-supervised adaptation without accessing source data. The code will be released later.
Abstract (translated)
远程光电容积描记（rPPG）作为一种利用摄像头监测生理信号的非侵入性方法，已经展现出广阔的应用前景。尽管已提出多种领域适应和泛化方法来提高基于深度学习的rPPG模型在未知部署环境中的适应能力，但在隐私保护和实时适应方面的考虑限制了其实际应用。因此，在这项工作中，我们旨在为rPPG任务提出一种全新的完全测试时间适应（TTA）策略。 具体而言，根据生理学的先验知识以及我们的观察，我们注意到不仅在频率域中存在rPPG信号的空间-时间一致性，而且在时域中的不一致也很显著。鉴于此，通过利用这两种先验信息，即一致性和不一致性，我们引入了一种创新的知识驱动自监督框架——**C**onsistency-\**i*n\**C**onsistency-\**i**ntegration（**CiCi**），以增强模型在推理过程中的适应能力。此外，我们的方法进一步整合了一个梯度动态控制机制，用以缓解先验信息之间的潜在冲突，确保实例间的稳定适应。 通过TTA协议在五个不同的数据集上进行广泛实验，我们的方法持续优于现有技术，在不访问源数据的情况下实现了实时自监督适应的最先进性能。代码将在后续发布。
URL
https://arxiv.org/abs/2507.07908
